1. Field of the Invention
The present invention relates to an apparatus and method for managing power conditions of a computer system. More specifically, the present invention relates to an apparatus coupled to a communication line to remotely control a power status of a remote device and a method for performing such remote power management.
2. Background of the Field
Throughout the last decade, business have realized that a networked system incorporating a desired number of workstations and at least one server is generally more cost effective than purchasing the desired number of stand-alone computers, each of which having a large internal memory. The networked system is typically a number of servers (e.g., computers, workstations, etc.) coupled through a communication line, such as a dedicated RS 232 line, to at least one server node. Hereinafter, a "server node" refers to any device which typically operates in cooperation with a server, including but not limited to a host server.
One problem associated with networked systems employing server nodes being large in size is that the server nodes are typically stored in remote computer rooms within the same building or perhaps even miles away, causing support difficulties. Thus, in order to control power consumption of the server nodes and to reboot server nodes if any of them have "frozen", support personnel had to physically "power-off" or "power-on" these server nodes. This support technique was not cost-effective because many support personnel are needed in order to support a multiple building corporation having tens or hundreds of server nodes. Moreover, it is time consuming for the support personnel to physically power-off or power-on the server nodes.
Recently, a company designed a conventional power switch (hereinafter referred to as the "IPC 3100") as shown in FIG. 1. The IPC 3100 1 is designed to remotely supply 110 volts of AC power ("110 VAC") through each of its four power outlets 2a-2d for use by a single host server as illustrated or up to four host servers. The IPC 3100 1 is powered by a conventional 110 VAC power supply 3 which is connected to the IPC 3100 1 through an AC power connection cord 4. The IPC 3100 1 transfers the 110 VAC to the host server 5 through at most four corresponding power connection signal lines of which only three lines 6b-6d are shown. Therefore, the IPC 3100 1 is incapable of supporting host servers having power requirements different than 110 VAC, such as 220 VAC and non-domestic voltage levels.
In a conventional networking scheme, a first serial port 8 of a terminal (i.e., console) server 7 is coupled to a first serial port 9 of the host server 5 through a first serial communication line 10, usually a RS 232 signal line. To install the IPC 3100 1 within the conventional networking scheme, new hardware is typically needed because the console server 7 requires a second serial port 11 for electrically connecting the IPC 3100 1 to the console server 7. Therefore, installation of the IPC 3100 1 is typically extremely difficult and costly to perform because the console server 7 normally does not have the unused second serial port 11. Even if the console server 7 has the unused second serial port 11, installing the IPC 31001 would require the serial port 11 of the console server 7 to be reprogrammed.
The next step for implementing the IPC 3100 1 is to install a second dedicated serial communication line 12 in order to electrically couple the console server 7 to the IPC 3100 1.
A final step for implementing the IPC 3100 1 is that support personnel must re-route each of the power connection signal lines 6b-6d which are directly coupled to the host server 5. For companies having tens or hundreds of console and host servers, purchasing, implementing and re-routing the above-indicated signal lines can be a costly and time consuming process.
As briefly alluded to above, there are many disadvantages associated with the IPC 3100. A first disadvantage is that the IPC 3100 is extremely difficult to install, and in some case, impossible to install. A second disadvantage is that the IPC 3100 is expensive to install. As discussed above, the IPC 3100 does not fully utilize existing hardware, but rather, requires additional hardware to be installed, if at all possible. As a result, implementing the IPC 3100 is costly in view of additional material costs (cables, serial ports, etc.) and labor costs associated with installation, especially for companies having tens or hundreds of host servers.
A third disadvantage is that the IPC 3100 has no power outage management features. The IPC 3100 1 is solely AC powered. In the event of a sudden power-outage, there would be no remote access to the host servers because no AC power would be available to the IPC 3100. The lack of remote access would require support personnel to physically power-off the host servers until power was restored. This lack of remote access during power outages subjects the host-server to severe damage if it experiences an electric spike. Although support personnel may be able to quickly reach a few host servers to protect them from potential damage, it is highly doubtful that the support personnel would be able to power-off every host server in the event that the electric spike occurs.
Another disadvantage is that the IPC 3100 can not be used to remotely control computers that do not require power other than 110 VAC. Therefore, the IPC 3100 does not support a wide range of computer systems.
Another disadvantage is associated with the IPC 3100 is that it functions at a slow baud rate of 2400 bps. Therefore, for a majority of machines capable of operating at a greater baud rates, the IPC 3100 would require limitations in the networked system's communication speed.
Furthermore, the IPC 3100 fails to provide a feature to effectively prevent users from remotely altering the power status of the host server while the host server is being repaired. Of course, this could be done by unplugging the second dedicated serial communication line, but then, there poses risks of damaging the serial port, the dedicated serial communication line itself as well as exposing the support personnel to difficulties in re-connecting the second dedicated serial communication line.